1.91k likes | 3.29k Views
Dynamics of Structures. Lecture 1 Anil K. Chopra Universidad de los Andes Bogotá, Colombia May 23, 2011. Simple System. Simple System. Free Vibration of Idealized Systems. Idealized Systems. Free Vibration. Decay of Free Vibration. Aluminum Model. Plexiglass Model. Equation of Motion.
E N D
Dynamics of Structures Lecture 1 Anil K. Chopra Universidad de los Andes Bogotá, Colombia May 23, 2011
Simple System Bogata, Colombia
Simple System Bogata, Colombia
Free Vibration of Idealized Systems Idealized Systems Free Vibration Bogata, Colombia
Decay of Free Vibration Aluminum Model Plexiglass Model Bogata, Colombia
Equation of Motion Single-Degree-of-Freedom System Bogata, Colombia
Lateral Stiffness Bogata, Colombia
Undamped Free Vibration Bogata, Colombia
Natural Frequency (Period) of Vibration Bogata, Colombia
Three-Story Steel Frame Building Bogata, Colombia
49-Story Steel Frame Building Period = 2.90 sec Bogata, Colombia
Golden Gate Bridge Bogata, Colombia
Pine Flat Dam, 400 ft high Bogata, Colombia
Damped Free Vibration • Damping Ratio • Equation of Motion Bogata, Colombia
Effects of Damping (<1) Bogata, Colombia
Effects of Damping Bogata, Colombia
Measurement of Period & Damping Bogata, Colombia
Example Bogata, Colombia
Vibration Generator Bogata, Colombia
Vibration Generator Bogata, Colombia
Measurement of Frequency & Damping Bogata, Colombia
Earthquake Ground Motions Bogata, Colombia
Earthquake Ground Motions Bogata, Colombia
Ground Acceleration, Velocity & Displacement Bogata, Colombia
Equation of Motion Bogata, Colombia
Structural Response Depends on Tn and Bogata, Colombia
Structural Deformation & Forces • Equivalent Static Forces • Pseudo-Acceleration • Internal Forces by Static Analysis Bogata, Colombia
Earthquake Response Spectrum • Peak Response • Plot of for fixed damping Bogata, Colombia
Deformation Response Spectrum Bogata, Colombia
Pseudo Velocity Response Spectrum Plot of V v’s Tn • 2 3 Tn, sec Bogata, Colombia
Pseudo Acceleration Response Spectrum Plot of A v’s Tn Peak Force Bogata, Colombia
Combined D-V-A Spectrum Bogata, Colombia
Combined D-V-A Spectrum = 0, 2, 5, 10, and 20% Bogata, Colombia
Pseudo-Acceleration Response Spectrum = 0, 2, 5, 10, and 20% Bogata, Colombia
Deformation Response Spectrum = 0, 2, 5, 10, and 20% Bogata, Colombia
Peak Response from Spectrum Internal forces by statics Bogata, Colombia
Example Bogata, Colombia
Example Bogata, Colombia
Example Bogata, Colombia
Response Spectrum and Peak Ground Accleration, Velocity, and Displacement Bogata, Colombia
Ground Acceleration, Velocity & Displacement Bogata, Colombia
Response Spectrum Plotted on Normalized Scales Bogata, Colombia
Mean Response Spectrum & Design Spectrum Bogata, Colombia
Construction of Elastic Design Spectrum Bogata, Colombia
Amplification Factors N. M. Newmark and W. J. Hall, Earthquake Spectra and Design, EERI, Berkeley, CA, 1982, pp. 35, and 36. Bogata, Colombia
Construction of Design Spectrum, 84th Percentile, = 5% Bogata, Colombia
Elastic Design Spectrum, 84th Percentile, = 5% Bogata, Colombia
Elastic Design Spectrum, = 1, 2, 5, 10, 20% Bogata, Colombia
Elastic Design Spectrum, = 1, 2, 5, 10, 20% Bogata, Colombia